About PureJSON

What is PureJSON?

PureJSON is a free, open-source collection of JSON tools designed for developers, data engineers, and anyone who works with JSON data. Every tool runs 100% in your browser — no server processing, no data collection, no account required.

Whether you need to quickly view a large JSON file, format messy API responses, convert JSON to other formats, or compare two documents, PureJSON provides fast, secure, and reliable tools right in your browser.

Why PureJSON?

Many online JSON tools send your data to a server for processing. This creates security risks, especially when working with sensitive data like API keys, credentials, or production configurations. PureJSON is different:

  • 100% Client-Side: All processing happens in your browser using JavaScript. No data is ever transmitted to any server.
  • Works Offline: PureJSON is a Progressive Web App (PWA). Install it and use it without an internet connection.
  • Free & Open Source: No subscriptions, no paywalls, no feature restrictions. The source code is available on GitHub.
  • Multi-Language: Available in English, Korean, and Japanese with full localization support.

Available Tools

PureJSON offers a comprehensive suite of JSON tools:

  • JSON Viewer & Explorer — Visualize JSON data in an interactive tree view with syntax highlighting
  • JSON Formatter & Beautifier — Format and indent JSON with customizable spacing options
  • JSON Minifier — Compress JSON by removing whitespace to reduce file size
  • Format Converters — Convert JSON to TypeScript, YAML, CSV, XML, and vice versa
  • JSON Diff & Sorter — Compare two JSON documents or sort object keys alphabetically

Technology

PureJSON is built with modern web technologies: SvelteKit for the framework, Monaco Editor (the same editor used in VS Code) for code editing, and Tailwind CSS for styling. The app is deployed on Cloudflare Pages for global performance.

The codebase is written in TypeScript with strict type checking, ensuring reliability and maintainability. All tools are thoroughly tested and optimized for performance, even with large JSON files.

Open Source

PureJSON is open source and welcomes contributions. Visit our GitHub repository to report bugs, suggest features, or contribute code. Together, we can make JSON tools better for everyone.